Sonar Depth Determination Using Sound Speed Profile Characteristic Points

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining sound propagation underwater require extensive computational and time efforts due to the need to calculate sound propagation for every equidistant sea depth, making it inefficient for rapid location or hiding of objects, such as submarines, especially in scenarios with abrupt changes in sound speed.

Innovation Solution

A method that selects characteristic points on the sound speed profile over sea depth where significant changes occur, calculates sound propagation only at these points, and determines the optimal sea depth based on signal-to-noise ratio for efficient object location or hiding, using a data processing device and navigation system.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If sound propagation is calculated for every equidistant ocean depth, then measurement precision is improved, but productivity deteriorates

Engineering Contradiction:
Improveaccuracy of sound propagation calculationVSAvoidcomputational efficiency
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent extracts only the essential calculation points (characteristic points where sound velocity changes occur) from the complete set of equidistant depth points. This selective extraction maintains measurement precision at critical locations while dramatically reducing the total number of calculations required, thus resolving the contradiction between accuracy and computational efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies local quality by concentrating computational resources at specific depths where sound velocity profiles exhibit characteristic changes, rather than uniformly distributing calculations across all depths. This localized approach ensures high precision where it matters most (at characteristic points) while reducing overall computational burden.

Inventive Principle:
Principle #3Local quality

2Measurement precision

If sound propagation is calculated for every equidistant ocean depth, then measurement precision is improved, but loss of time worsens

Engineering Contradiction:
Improveaccuracy of sound propagation calculationVSAvoidtime for determining optimal depth
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent extracts only the essential calculation points (characteristic points where sound velocity changes occur) from the complete set of equidistant depth points. This selective extraction maintains measurement precision at critical locations while dramatically reducing the total number of calculations required, thus resolving the contradiction between accuracy and computational efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent performs preliminary identification of characteristic points in the sound velocity profile before conducting full sound propagation calculations. This preliminary action allows the system to pre-determine where calculations are necessary, avoiding wasted computational time at depths where characteristic changes do not occur, thereby reducing overall time loss while maintaining precision.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If data processing is performed for all ocean depths, then measurement precision is improved, but device complexity worsens

Engineering Contradiction:
Improveaccuracy of optimal depth determinationVSAvoidcomplexity of data processing system
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts only the essential calculation points (characteristic points where sound velocity changes occur) from the complete set of equidistant depth points. This selective extraction maintains measurement precision at critical locations while dramatically reducing the total number of calculations required, thus resolving the contradiction between accuracy and computational efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the parameter selection criterion from fixed equidistant depth intervals to variable characteristic points based on sound velocity profile changes. This parameter transformation simplifies the data processing requirements by adapting the calculation locations to the actual physical characteristics of the medium, reducing device complexity while maintaining measurement precision.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach allows for quicker determination of optimal sea depth, enabling rapid location or hiding of objects and prompt reaction to changes in sound speed, significantly reducing computational and time expenditures.

Implementation Method 1

Sound does not propagate homogeneously through water, as the speed of sound changes within the water column and/or with the depth of the sea

Methodology Applied
Scientific EffectSound propagation: Sound

Implementation Method 2

The speed of sound propagation is primarily a function of the density, temperature, salinity, and pressure of the water. Temperature and pressure are the most significant influencing factors

Methodology Applied
Scientific EffectSpeed of sound variation: Speed of Sound

Implementation Method 3

sound is reflected or diffracted at the water's surface and/or the seabed

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 4

sound is reflected or diffracted at the water's surface and/or the seabed

Methodology Applied
Scientific EffectDiffraction: Diffraction

Implementation Method 5

when passing from a layer with a high sound velocity to one with a low sound velocity, the sound waves are diffracted towards the vertical

Methodology Applied
Scientific EffectRefraction: Refraction

Data Source

PatentEP3384314B1Method for determining an optimal sea depth, sonar device and water vehicle
Publication Date: 2021.10.06 ATLAS ELEKTRONIK GMBH
  • EP3384314B1 patent drawingFigure 1
  • EP3384314B1 patent drawingFigure 2
  • EP3384314B1 patent drawingFigure 3

AI summary

The invention relates to a method for determining an optimum sea depth for locating and/or hiding an object under water by means of a data processing device and/or a navigation device, having the following steps of: selecting a profile of a speed of sound above a sea depth for a coordinate from a database or determining the profile of the speed of sound above the sea depth for the coordinate, selecting characteristic points, in particular a minimum and/or a maximum, on the profile of the speed of sound above the sea depth, carrying out a method for calculating sound propagation by means of an algorithm in the data processing device and/or the navigation device for propagation of the sound energies of a transmitted and/or received sound signal at the selected characteristic points, determining a distance-dependent signal-to-noise ratio of the determined sound energies for the selected characteristic points, determining the optimum sea depth on the basis of the signal-to-noise ratio of the determined sound energies for detecting and/or hiding an object under water. The invention also relates to a sonar system having an antenna for transmitting and/or receiving waterborne sound signals, and to a watercraft.